Apparatus



Sept. 18, 1951 a. 8. SWEET 2,568,373.

APPARATUS FOR MANUFACTURING CLOTHESPINS Filed Aug. 30, 1949 I IINVENTOR.

i l 47 BERT .B. 5'WET 69 fly. -6'

7| W 70 25 ATTORNEY Patented Sept. 18, 1951 armaaruslron MANUFACTURING.onornssrms:

BertB. Sweet, Akmmflhio. g

, Application. August 30, 1949'; Serial'--No.-1'13,122'

I'Claim.

This invention relates to apparatus for producing metal clothes pins.

The clothes pin is preferablygforme'd'by doubling a narrowyflat'stripofmetalat its middle:

The legs of" the clothes pin are straight'except that they areflaredsligh tly attheir'outer ends; Preferably the legs are not"parallelbut diverge slightly from'the arched'portion which connects thetwo'legs, making the'pin somewhat wedgeshaped. The farther a, clothesiine-is forcedbetween the legs of the pin the tightert-he'pin wi-ll*grip the line. Preferably the inside surface of each leg-isembossed'orotherwise roughenedto give added holding power.

This pin has 1 many advantages over'the conventional wooden or plasticplus new on the market. It is small, for example, about one-arid=one-half inchtlong, andlight, so that a number of themmay be held inone-hald. Being metal,

it is. easily cleaned and inexpensively manufactured.

The clothes pins maybe manufactured. -advan-- tageously on at massproduction basis with 1 the preferred apparatus ofzthis invention.This-prefer-red. apparatus includes a :novel, I single-action dieandcorresponding punches therefor. They" are adaptable toconventional-punch presses.- The. stock from which: the pins are-"madeis fed into the pressirom a. roll in the -form of arcan tinuous. ribbon.Onasingle stroke of the press},

a suficient' length of the stock for: the formation ofrarclothes. pinsheared from this ribbon-=and then doubled toform the pin.Embossing-rollers form depressions onlthe outer surface ot-each leg--and bossesv on the. innersurface,:asthe'materialis.;doub1ed.. Thefinished pin is ejected-as: the punches move upward and then more ofthestockis fed .iIlbQxPl'OPGIYPDSitiOII on the-die ready for a repetitionof theabove; operation. No handling of the pin is necessary. It iscompletely-formedin one operation.

The invention-will be further described with reference to theaccompanying drawings, -1'n which-* Fig. 1 is a side elevation of theclothes pin;

Fig. 2 is a view taken from'the right side of.

Fig. 1;

Fig. 3 is an enlarged cross-sectional view of, a,

leg ofthe pin taken-on the;liner3 3 01' Fig. 1;

Fig. 4 is an enlarged cross-sectional view taken Figs-.5. isa;plan-view;oiwamreierred die us ddn the manufactureoit ehm Fi (i ista.crossesectiehal :iroht-ielevation :of the die and: punohesttherefor-ataken on: the line: 6-26 oilFigs'l; excepkthatithedimand P13161185:

as shown in Fig- 6. area-in clo cdirnosition;

die. and shapin punch showing them in: open position;

Fig. .8 islan enlareedsplanrviewrottheedie rollerswhichshepthelaoutsidezof theme:

Fig.1 .9 is an: enlar edplan-view;ofithewembossine; rollersof the die;

Fig. lilaisian -enlarged crossesectionalxviewsef the shapinspunch:taken. on-;the.=.-line lo-em of;

Rig, 11 iszan enlar ed CIQSSeSEQtiQIlM IViBWzjOfT the c f p nhtakenaalong line I 4-4 I. of.:-Eig.- 1, and

Fi 12 1 is an enlarged ;.,side.a levat.ion of the lower end ofhercutsofiinuneh- The clothes: pin Isis termed of.- aznarrow...:flatstrip of i resilient. metal. .cpreierably steel or ale-.- minumTheglegsrii of-xthepinare connected .together. atgonerendgbyz-theaarchediportlonrll. The: legs are substantially straightand\fiat;.thr0ugh-- outtheir length exceptthatmhe-outenend oheach isflared-slightlyet 5150; thatstheyl .m-ayz beeasily slipped over aclothes line. Theseengzls;greed v vantaee us y. nly -sl ght wilaredlII.;more-l:.than slightly flar d swhena numberro :nihsare pac ed intoalboxr-thaflered -end .ofalegof one pm? easily becomesitightly. jammed.between the; less of otherv pinsin the box, so that:the are 1diflicult.

to separate.

Preferably the-legs ar notparallel but-diverge liehtly from.:thearchA.TheIO BPGIIdQffifi'QD' leg. is also radiused, at..1..and.:the outside.corner 8 alone he longitudinal. edeesllofreaeh 1 98.: are

rounded.

A plurality of parallel.lateralerooves, H are pressed'into theoutsidesurface-of each leg; oft-la pinaas itis shap d. The, insi e-surfacedeachleg is embossed with. parallel b05585.l3,,,aGl1-b5-- ing opposite,one, of the grooves I I ,as .shownin Figs.,3 and w i. The grooves! Iroughen. the-Outer 1' surface of the legs and makethem easily; rasp d;

whenthey arebeingslippedonto a. clothes line 3 or removed therefrom. Theembossed inner surface gives the pins a stronger grip when fasteningclothes to a clothes line.

The die used in the manufacture of these pins is provided with a stockcut-off matrix 20, a shaping matrix 2|, and a stop 22 which measures thelength of stock needed to form one pin. These matrices are fastened to asuitable die shoe 24 which in turn is mounted to the bed or bolster 25of a punch press 21. The punches 30 and 3| used in conjunction with thematrices 20 and 2| respectively are bolted to punch shoe 33 which inturn is fastened to the reciprocating head 34 of the punch press.Cut-off punch 3|] moves into and out of matrix 20 and shaping punch 3|moves into and out of matrix 2| as the head of the press reciprocates.Vertical guide pins 36 are provided at the rear corners of the die shoe.These slide into appropriate openings in the punch shoe and keep eachpunch properly aligned with its respective matrix during the impactstrokes of the press.

In forming the pins, the stock, a metal ribbon 38, is fed from a. roll39. This stock is brought across the top of matrices 20 and 2| and theend of the stock fits into the recessed portion 4| of the stop.

As the head of the press moves down at the start of an operating stroke,cut-off punch 36, being slightly longer than shaping punch 3|, strikesthe ribbon'of stock'first. The cutting edge 43 (Fig. 12) of this punchis notched slightly at 45 where it contacts the stock so that the stockis centered properly on each stroke of the press. Opposite sides ofpunch 30 are provided with concavities 46, the radius of each beingequal to the radius 1 at the end of each leg. The cut-off matrix 20 isformed of two upright plates 41 disposed laterally of the die shoe. Theinner face of each plate is provided with a convex boss 49, alsosubstantially equal to radius I. Cut-off punch 30 moves up and downbetween the plates 41 with the co'ncavities 46 in mating relation withthe convex bosses 49; there being sufficient clearance between them sothat the punch does not contact any portion of the matrix.

Cut-off punch 30 strikes the stock 38 and shears through the portionbetween the sharp edges around the top of'each boss 49. This punch formsa radius I on the end of the length of stock out off to be doubled toform a pin, and also on the end of the stock strip which will be movedacross the matrices and into recess 4| of the stop at the start of thenext succeeding stroke of the press. A recess (Fig. 6) is provided inthe die shoe between plates 41 to collect the cutout scraps.

Immediately after the cut-off punch 30 shears off themeasured length ofthe ribbon, the end of the shaping punch 3| strikes it and doubles it byforcing its mid-section into the matrix 2|. This matrix is'provided withtwo parallel rollers 54 between which the punch 3| moves up'and down,and these are supported between the parallel plates 56. The centerportion 51 of each roller is of smaller diameter than the remainder ofthe roll and the shoulder at each side of this center section isradiused at 59. These rollers double the length of stock when punch 3|forces it between them. The radiused portions 59 compress the edges ofthe stock to form the radius the rollers.

stock between rollers 54 it forces it between rollers 6|, and teeth 62bite into the metal surface and form the grooves II on what will be theoutside surface of the finished pin. The lower central portion ofopposite lateral surfaces of punch 3| is undercut a few thousandths ofan inch at 64 (Figs. '7 and 10) so that as the teeth form the grooves,the metal opposite each groove is bulged out slightly into this undercutarea 64, forming a boss I3 on the inside surface of each leg of the pinopposite each groove I.

Fig. 6 shows the die and punches in closed position after a pin iscompletely shaped. The lower edge of punch 3| is rounded somewhat toform the arch 4 of the pin. The upper portion of each side of the punchis curved outwardly at 68 to form the flared ends 5 of the finished pin.

An ejector69 is provided in die shoe 24 and is enclosed in a tube whichprojects below the die shoe through the hole 10 in the center of thebolster. This ejector extends upwardly between As punch 3| forces thelength of stock down between the rollers it compresses spring ll locatedunder the base of the ejector. When the punch is withdrawn from thematrix this spring expands and lifts the ejector which holds the newlyformed pin in contact with the punch until the pin is clear of thematrix. The conventional presses used for dies of the type describedmaybe adjusted to operate with the bolster plate at an angle to thehorizontal as shown in Fig. 7. Operating at such an angle, as soon asthe newly formed pin is clear of the ejector, it will drop off punch 3|into a suitable hopper or tray 13.

To summarize the method of forming the clothes pin, the stock forforming a pin is first measured from a roll and then this length issheared off by a die punch which enters a cutoff matrix of the die justas the head of the press starts downward. This punch rounds the ends ofthe length of stock. Immediately thereafter a second punch doubles thispiece by forcing the middle portion of the stock into a shaping matrix.The pin is properly shaped, the outer edges are rounded, grooves areformed on the outer surface of the legs and the inner surface isembossed, all in oneroperation. On the return stroke of the press, theejector removes thefinished pin and the equipment is clear and ready fora repetition of the operation as described.

Modifications may be made in the equipment without departing from thescope of the appended claim. For instance, it is not essential that theouter corners of the pin be rounded. It

is not necessary that the bosses l3 be formed on the inner surface ofthe pin, although this makes the pin more eflicient. In the equipment,any suitable automatic feed, properly timed with the action of thepress, may be used for supplying stock to the die. to fasten clothes ona clothes line, the pin may be used for fastening draperies and thelike, and for other uses.

What I claim is:

Apparatus for manufacturing a clothes pin from a flat metal strip, whichincludes a pair of spaced. parallel rollers, and adjacent theretoasecond pair of spaced parallel rollers, the opening between the firstpair of said rollers being in register with the opening between thesecond pair of said rollers, the central portion of each roller of thefirst pair being of smaller diameter than the end portions and theshoulders at each end of the Although particularly designed.

central portion being radiused to round the corners of the pin, and eachof the rollers of the second pair having radially projecting teeth onthe periphery, and a punch for reciprocating into and out of the spacebetween the pairs of rollers, the Walls of the punch outwardly adjacentthe portion between the first pair of rollers at the end of the inwardmovement of the punch being flared slightly outwardly, the centralportion of the punch opposite the teeth being undercut.

BERT B. SWEET.

REFERENCES CITED The following references are of record in the file ofthis patent:

Number Number Australia July 1, 1946

